Feeder for dividing and distributing fluids



Oct. 19, 1943; G. NEMETZ 2,331,924

FEEDER FOR DIVIDING AND DISTRIBUTING FLUIDS Filed Dec. ll, 1940 2 Sheets-Sheet 1 I my; 121w INVENTOR: GUSTAV NEMETZ B W ATTORNEY Get. 19, 1943. N M 2,331,924

FEEDER FOR DIVIDING AND DISTRIBUTING FLUIDS Filed Dec. 11, 1940 2 Sheets-Sheet 2 INVENTOR; GUSTAV NEMETZ BY W 4- A41 7 ATTQRNEY. A

Patented Oct. 19, 1943 FEEDER FOR DIVIUIN G FLUIDS AND DISTRIBUTING Gustav Nemetz, Vienna, Germany; vested in the Alien Property Custodian Application December 11, 1940, Serial No. 369,597 In Germany February 21, 1939 3 Claims.

The present invention relates to a feeder for dividing and distributing fluids containing in a casing two double-acting pistons each reciprocated by the pressure of the fluid within a separate cylinderbore closed at both ends, said pis;

tons delivering successively predetermined amounts of fluid out of four operating chambers formed by said pistons to respective outlets. The fluid supplied by a source of pressure is thus distributed to four outlets in portions corresponding to the cross-sectional area of the pistons andto the piston strokes.

In such devices, each piston controls, in the manner of an axially operated piston valve, channels by means of edges of recesses provided on its cylindrical surface. Some of said channels lead from said operating chambers to the cylinder bore of the other piston. Other channels lead from other points of the cylinder bores to the source of pressure fluid. Outlet passages are provided leading'from other-points of the cylinder bores to the points of use of the apportioned fluid. In conventional devices of this kind a locking member is provided and two special recesses for said locking member in each of the two pistons. These recesses are so constructed that one of said recesses in that piston, which reaches an end position, will receive one end of the locking member, when the other piston pushes said locking member out of its cylinder at the beginning of its delivery stroke. The locking member thus alternately locks one piston in its end position, while the other piston carries out its operating stroke.

In conventional devices of the kind described the locking member consists of a pin conically tapered at each end and slidably disposed in a transverse bore rectangularly connecting the two cylinder bores in the casing, and adapted to enter alternately into annular .grooves a pair of which is provided on the cylindrical surface of each piston. One of the grooves of each pair of grooves receives the end of the lockingmember facing it at one end position of the piston and the other groove at the other end position. The locking member is displaced by the pressure" exerted by a flank of the respective groove upon the conical end of the locking member facing it. Y With this arrangement there is merely a knife-edge contact, which at higher counterpressures at the points of use will owing to the heavy friction frequently result in both pistons being locked by the locking member and in a failure of the device.

In order to remedy this drawback, the recesses of the pistons and the ends of the locking member engaging in them are, according to the present invention, provided with broad surfaces producing a broad surface contact when the locking member cooperates with the walls of the said recesses of the pistons. To this end, said recesses of the pistons are provided with flat operating surfaces and the locking member. is likewise provided at its ends with corresponding flat surfaces. Alternatively, the locking member may be provided with outwardly, curved surfaces and the recesses of the pistons with correspondingly inwardly curved operating surfaces. assure that the recesses of the pistons will invariably face the respective end of the locking -member, the pistons are prevented by special means from rotating about their longitudinal axes during their movements. v

The drawings show two embodiments of the present invention by way of example.

Fig. 1 is a diagrammatic sectional view of a form of the device longitudinally taken through the cylinder bores, in whichv the ends of the locking member and the recesses of the pistons cooperate by means of flat surfaces, and in which either piston is prevented from rotating about its axis by a special device. Figs. 2 and 3 are two different views of a piston used in the device illustrated in Fig. 1. Figs. 4-6 are three different views of the locking member used in the 7 device illustrated in Fig. 1.

Fig. 7 is a diagrammatic longitudinally sectional view of an alternative embodiment of the invention in which the pistons are prevented from rotating about their axes by means of the locking member. The form of the respective pistons is shown in Fig. 8.

In all figures like numerals are employed to designate like parts. v

In the casing of the device, two pistons l and 2 are movable in bores 3 and 4, the ends of which are closed by plugs 5, 6, 1, 8 whereby four operating'chambers or cylinders I, II, III, IV are formed. From each of these operating chambers, a channel 9, 9, 9", 9" respectively leads to the cylinder for the other piston. From each cylinder 3 and 4, two further channels II), It' and I0", I0 respectively" lead to outlets communicating with the points of use of the fluid distributed by said device. A channel II which is fed with fluid under pressure by a source of pressure (not shown) opens into a transverse bore 42 connecting the cylinders 3,4. Slidable in said transverse bore is a locking member l2 consisting of a cylindrical pinhaving wedge shaped In order to I ends, two longitudinal grooves 4|], 4I and a transverse bore 44 connecting said grooves. Each of the pistons I, 2 is provided with two recesses I3, I4 and I5, I6 respectively which communicate with the bore 42 and, therefore, with the pressure fluid reservoir. The recesses I3 and I5 are delimited below and the recesses I4 and I6 above by oblique surfaces 35, 32, 38, 34 respectively. The piston I is provided with a recess at IT and I8, the piston 2 at I9 and 20. Plugs 50 screwed into the casing project into the cylinders III, IV respectively with flat end surfaces, which nearly touch the surfaces I06, 2% provided on the pistons I, 2 parallel to their axes. The edges 2|, 22, 23, 24, and 25, 26, 21 and 28 of the pistons I and 2 are controlling edges which control the channels 9, 9, 9", 9" and the outlets III', III' and III, III in the following manner, when the pistons I and 2 are moved by the pressure of the fluid emerging from the channel II.

In Fig. 1, the piston I is in its upper end position, while the piston 2 is just passing its inter: mediate position. When the pistons occupy these positions the fluid will flow out of the chamber I3 of the piston I through the bore 9, which is uncovered by the controlling edge 22, to the operating chamber or cylinder II.

At the, same time the operating chamber IV is connected to the outlet III' by the bore 9" and the hollow space around the reduced por-- tion I8 of the piston I, and there is, therefore, either no pressure in it or the pressure prevailing at the point of use connected to the outlet 3', which is lower than the pressure within the fluid reservoir. The piston 2 will, therefore, move downward, the fluid being pushed out of the operating chamber IV through the channel 9", and the hollow space around the reduced portion I3 of the piston I to the outlet III' and to the point of use.

When the piston 2 has reached its lower end position, its controlling edges and 21 uncover the channels 9" and 9. The fluid will now flow out of the recess I5 of the piston, on which acts the pressure of the fluid from its source, into the operating chamber or cylinder I, and the fluid will be forced from the operating chamber or cylinder III through the channel 9" and the hollow space around the reduced portion I9 of the piston 2, with which it is new in communication, to the outlet Ill". During the downward motion of the piston I, the piston 2 remains stationary in its lower end position. Its recess I5 will then be situated just opposite the right-hand end of the locking member I2, and the latter will be displaced by the inclined surface 29 of the recess I4 of the piston i, which contacts with the surface 3D of the left-hand end of the locking member, to the right side within the bore 52, entering with its right-hand end into the recess it of the piston 2.

In this manner the locking member i2 controls the movement of the two pistons I and 2 by locking the controlling piston in its end position until the piston executing the delivery stroke has completed its stroke.

When the piston I has reached its lower end position, its recess I4 communicates with the channel 9",which is then uncovered by the controlling edge 23. Now, the operating chamber or cylinder IV is supplied with fluid under pressure and the piston 2 begins to move upward, thus forcing the fluid out of the operating chamber II through the channel 9 and the hollow space of the reduced portion II of the piston I communicating with it, into the outlet III. At the same time, the locking member I2 is displaced to the left side by the cooperation of the surfaces 32 and 3|, the left-hand of the locking member I2 engaging in the recess I3 of the piston I and locking the latter in its lower end position; This operation continues in a cycle, all the four operating chambers becoming operative by rotation and ejecting predetermined quantities of fluid to the outlets associated with them.

As appears from the above description, theflat surface 29, 35 of the recesses in the piston I and 32 and 34 of the recesses in the piston 2 cooperate in this case with the surfaces 30, 3 6 and 3|,-31 respectively of the locking member I2 by making a surface contact, which ensures that no undesirable reciprocal jamming and locking of the pistons I and 2 and the locking member I2 can take place. The recesses I3, I4, I5 and I6 of the pistons intended for the reception of the ends of the locking member will invariably facethe ends of the locking member, as the pistons I and 2 are prevented from rotating about their axes'by'the surfaces I00, 200 of the pistons and the faces of the plugs 50.

In order to save such special elements for preventing the pistons I' and 2 from rotating about their axes, the locking member I2" may be utilized for this purpose. A constructional form of a distributing device of this kind is shown in Fig .7.

Between the recesses I3" and I4 of the piston I, a surface 33 is provided parallel to the piston axis, and a similar surface 33 between the recesses I5" and I6" of the piston 2'. During the longitudinal movements of the piston 2, the

edge-shaped end 39" of the locking member I2 is situated transversely to the piston axis closely opposite to the surface 33, preventing the piston 2 from rotating about its axis. The locking member I2" is likewise prevented fromrotating about its axis, for in this position one of the surfaces or 36 provided on its left-hand end will invariably contact with the surface 29' of the recess I4" and with the surface of the recess I3" of the piston I respectively. In a like manner, the transverse edge 38" of the left-hand end of the locking member prevents the piston I from rotating about its axis during its delivery stroke, due to its position closely opposite to the surface 33 of the piston I. The form of the pistons is shown in the different views of the piston 2' in Figs. 7 and 8.

In the distributing devices shown in Fig. '7, the locking member can only assume positions in which the left-hand end of the locking member projects partly into the cylinder I and the righthand end partly into the cylinder II. At these positions of the locking member, it would not, however, be possible to insert or withdraw the pistons, for if, for example, the locking member I2! is so located in the bore 42 that its left-hand end 38 engages recess I4" of piston I, and provided this recess is only of such depth as required With the constructional form treme end positions of the pistons which arev permissible in normal operation. The locking member can be inserted or withdrawn through the opening in the casing sealed by plug 50, when piston 2 is removed, .v

The construction shown is susceptible of modifications without departing from the-scope of the invention. -Thus, the passage H may also open into the cylinders III, IV within the range of the recesses of the respective piston.

What I claim is:

l. A feeder for dividing and distributing fluids comprising in a body member two cylinders closed at their ends, a reciprocating piston in each cylinder forming two. pump chambers, two discharge ports in each cylinder, a transverse passage connecting the two cylinders at, points situated between said two discharge ports,, an inlet port and two pairs of passages for feeding said pump chambers, said passages individually leading from one of the pump chambers to a point of the other cylinder situated between the opening of said transverse passage and a discharge port, a pair of recesses in each of said pistons for controlling the flow of the fluid through said passages, a further pair of recesses in each of said pistons adapted to pass the openings of said transverse passage during movements of said pistons and comprising substantially fiat surface means sloped with respect to the longitudinal axis of said pistons, a locking member longitudinally slidably disposed within said transverse passage and having substantially wedge shaped end portions alternately inserted into one of said further recesses and having surface means parallel to and alternately slidingly engaging said first mentioned surface means and preventing one piston from leaving its controlling position until the end of the movement of the other piston, and guide means individually associated with said pistons and with said body member and preventing rotation of said pistons I and assuring proper cooperation of said surface ments of said pistons, a locking member longitudinally 'slidably disposed within said transverse passage and having end portions alternately inserted into one of said further recesses and preventing one piston from leaving its controlling position until the end of the'movement of the other piston, said end portions having sloped surfaces terminating into a straight edge extending at right angle to the longitudinal axes of said locking member and of said pistons, said further recesses comprising sloped surfaces being in parallel relation to and individually slidingly engaging said first mentioned surfaces and preventing rotation of said pistons and of said looking member during engagement of said sloped surfaces, and a flat surface on said pistons between said sloped surfaces of said further recesses and being in parallel relation to the axes of said pistons for slidingly engaging said straight edge and preventing rotation of said pistons when said sloped surfaces are not in engagement.

3. A feeder for dividing and distributing fluids comprising in a body member two cylinders closed at their ends, a reciprocating piston in each cylinder forming two pump chambers, two discharge ports in each cylinder, a transverse passage connecting the two cylinders at points situated between said two discharge ports, an inlet port and two pairs of passages for feeding said pump chambers, said passages individually leading from one of the pump chambers to a point of the other cylinder situated between the opening of said transverse passage and a dis charge port, a pair of recesses in each of said pistons for controlling the flow of the fluid through said passages, a further pair of recesses in each of said pistons adapted to pass the openings of said transverse passage during movements of said pistons and comprising substantially fiat surface means inclined with respect to the longitudinal axis of said pistons, a locking member longitudinally slidably disposed within said transverse passage and having substantially wedge shaped end portions alternately inserted into one of said further recesses and being provided with substantially flat countersurfaces inclined with respect to the longitudinal axes of said pistons and of said locking member and parallel to and individually, slidingly, and flatly engaging said first mentioned surfaces and preventing one piston from leaving its controlling position until the end of the movement of the other piston and preventingrotation of said locking member and of said pistons during engagement of said surfaces.

GUSTAV NEMETZ. 

